BLF or Busy Lamp Field

What are Busy Lamp Fields or BLFs?

BLF or Busy Lamp Fields are typically a collection of indicators on a phone that show who is talking on other phones connected to the same PBX and typically used by a receptionist or secetary to aid in routing incoming calls.

To configure phone keys via the Hosted Platform simply do the following:

  1. Ensure the device is provisioned through VoiceHost (devices are listed in the portal under "provisioning"
  2. Find the device in the list you wish to configure the keys for.
  3. Select "Provision Keys"
  4. Select "BLF" from the drop-down and enter your account number followed by * and the extension you wish to see example 12345*204
  5. Save and reboot the phone ensuring that the checkbox for function keys is enabled.

Official Telephone Handset BLF Key Labeling Templates

You can download a formatted Key Labelling template for your Telephone Handsets below:

NOTE: These are pre-formatted to replace the paper BLF name inserts on your phone and should not be altered in size or scale.

VoiceHost Telephone handset BLF Key Labeling Templates
ManufacturerModel (click to download .doc .pdf)
Snom 3xx Series  7xx Series  720 | D725 | 760 | D765 
Cisco SPA500S Attendant Console sidecars  7861  
Polycom VVX Expansion Module    
Yealink SIP-T38G , SIP-T28P , SIP-T26P , IP Phone Expansion Module EXP38   
Grandstream GXP 1628 | 1630   
Panasonic KX-UT133 | KX-UT136   

Softphone BLF Functionality

Under 'Quick Dial' add the contacts you wish to monitor using the method prescribed at the top of this page.

Detailed Softphone instructions can be found here:

VoiceHost Softphone BLF


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